Unless of course the dropped calls were due to a firmware bug that had nothing to do with signal strength.
True Story:
A few years back - my company had just switched to using the Treo 700w ( yes a windows phone - but hear me out..

) with Sprint with the anticipation of Sprint to update/upgrade their network to 3G within the next month.
I was one of the lucky ones in my company to receive one of the first batch of 700w's. Happily - I switched out phones - got on the network and....
Nothing. Well - sort of nothing. The 3G connectivity was sketchy and constantly swapping between the 3G and Sprint's "older" network - can't remember what it was (maybe Edge as well?). I'd get dropped calls during driving, etc. Network performance was ok - however - even sitting in the same spot and not moving, watching the bars at the top - it would constantly switch between 3G/"edge". Battery life was abysmal - compared to the Treo 700p's that we had been using before. We even tried swapping phones for new ones to see if that resolved the issue..
So - we reported this to our rep - she stated that there was an "update" coming out in the next month or two. So we continued using the phones, waiting on the update. Looking around on the 'net on the forums at the time proved to indicate that we weren't the only ones experiencing the issue. However - it was noted that some users had no issues at all.
After about 2-3 months - the forums that I had been monitoring indicated that there was a new update/firmware for the 700w that should help out with the issues.. We checked with our rep and installed it - and overall - that appeared to help. However after a few days - still same issues (3G Swapping/Battery/call issues)... Which was strange as, according to the rep, there was a Sprint 3G tower very near where I lived and I should be getting a consistent/strong signal all the time.
We checked with our rep - and she had a forced refresh from Sprint to the phones issued.. From my "general" understanding - this was a master "list" of cell towers (or preferences -can't remember) that the phone keeps in it's memory, etc., to determine which signal to use for which tower, etc.
Immediately - the 3G signal was just "solid" - like night/day. Battery life was *much* improved going forward (the network swapping is what was actually killing the battery). Downloads were rock-solid, etc. Our exchange push email (new at the time) started working like a charm.
Now - this past week - I had just purchased an iPhone versus a Black Berry - primarily due to the fact that I wanted additional functionality that the Black Berry couldn't provide. It was somewhat of a hard decision, as I had heard about the the dropout issues, etc. When getting the iPhone home the first day - I was disappointed to see that I was experiencing the same reported issues - especially of note was the constant swapping of Edge/3G on my phone (my experience would be - it would connect to 3G - be fine for approximately 1-3 minutes - then you'd see it swap to Edge and/or no service).
Since I had experienced this before with the 700w - I figured I'd take a wait and see approach with the upcoming release. After installing the release - I've had the same experience as everyone else - much improved network connectivity (no swapping so far) - no dropped calls since the upgrade - and improved battery life.
Time will tell ( I still have about 20 days to see how it goes and am hoping this is the last of the issues..

)...
My thoughts here are - network-wise - the iPhone was experiencing the same issues/problems as the 700w. To the point above - I wouldn't call it a firmware bug - but more or less a configuration issue... and I don't believe it was ever an issue regarding signal strength due to other forum discussions and the fact that between the 2 networks - I had a solid signal - the phone just couldn't decide which network to stay on..
One other thing - it was later noted by our rep (much, much, later in an "hey you remember this issue?" conversation) - that the initial batch of phones/network was in a "test mode" of sorts at the time 3G was turned on - I also think that's the case here as well ( considering the 3G iPhone was only released about 2 months ago )
End of Story...
